java.awt.choice and extends canvas - in c# how?

[chuawenching]

I had 4 questions as i am trying to convert into c#.

In c#, it is slightly easy as drag and drop.

1) java.awt.Choice

imports java.awt.*;

Choice haha;

haha = new Choice();
haha.addItem(Float.toString((float) 0.05);

later,

Panel controlPanel = new Panel();
controlPanel.add(haha);

So what is Choice haha in c#?

2) I had a class that extends Canvas

class ACanvas extends Canvas
{
Image image;
Color color;
...
...
}

So how can i code Canvas in C#?

3) in C#, you can code class or struct. But in java, you only can code class.

So how do i know if i am converting a java code, which to struct and which to class?

4) ref value

I check some google website http://www.javacamp.org/javavscsharp/refparam.html

it states that in java code:

static void haha (int a, int b)

so in c#, i need to code this,

static void haha(ref int a, ref int b)

Can't i just code like java without ref keyword?

Thanks.

Regards,
Chua Wen Ching